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-rw-r--r--sound/drivers/serial-u16550.c1031
1 files changed, 1031 insertions, 0 deletions
diff --git a/sound/drivers/serial-u16550.c b/sound/drivers/serial-u16550.c
new file mode 100644
index 000000000..3947f084d
--- /dev/null
+++ b/sound/drivers/serial-u16550.c
@@ -0,0 +1,1031 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * serial.c
+ * Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
+ * Isaku Yamahata <yamahata@private.email.ne.jp>,
+ * George Hansper <ghansper@apana.org.au>,
+ * Hannu Savolainen
+ *
+ * This code is based on the code from ALSA 0.5.9, but heavily rewritten.
+ *
+ * Sat Mar 31 17:27:57 PST 2001 tim.mann@compaq.com
+ * Added support for the Midiator MS-124T and for the MS-124W in
+ * Single Addressed (S/A) or Multiple Burst (M/B) mode, with
+ * power derived either parasitically from the serial port or
+ * from a separate power supply.
+ *
+ * More documentation can be found in serial-u16550.txt.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <sound/core.h>
+#include <sound/rawmidi.h>
+#include <sound/initval.h>
+
+#include <linux/serial_reg.h>
+#include <linux/jiffies.h>
+
+MODULE_DESCRIPTION("MIDI serial u16550");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("{{ALSA, MIDI serial u16550}}");
+
+#define SNDRV_SERIAL_SOUNDCANVAS 0 /* Roland Soundcanvas; F5 NN selects part */
+#define SNDRV_SERIAL_MS124T 1 /* Midiator MS-124T */
+#define SNDRV_SERIAL_MS124W_SA 2 /* Midiator MS-124W in S/A mode */
+#define SNDRV_SERIAL_MS124W_MB 3 /* Midiator MS-124W in M/B mode */
+#define SNDRV_SERIAL_GENERIC 4 /* Generic Interface */
+#define SNDRV_SERIAL_MAX_ADAPTOR SNDRV_SERIAL_GENERIC
+static const char * const adaptor_names[] = {
+ "Soundcanvas",
+ "MS-124T",
+ "MS-124W S/A",
+ "MS-124W M/B",
+ "Generic"
+};
+
+#define SNDRV_SERIAL_NORMALBUFF 0 /* Normal blocking buffer operation */
+#define SNDRV_SERIAL_DROPBUFF 1 /* Non-blocking discard operation */
+
+static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; /* Index 0-MAX */
+static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; /* ID for this card */
+static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE; /* Enable this card */
+static long port[SNDRV_CARDS] = SNDRV_DEFAULT_PORT; /* 0x3f8,0x2f8,0x3e8,0x2e8 */
+static int irq[SNDRV_CARDS] = SNDRV_DEFAULT_IRQ; /* 3,4,5,7,9,10,11,14,15 */
+static int speed[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 38400}; /* 9600,19200,38400,57600,115200 */
+static int base[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 115200}; /* baud base */
+static int outs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
+static int ins[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1}; /* 1 to 16 */
+static int adaptor[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = SNDRV_SERIAL_SOUNDCANVAS};
+static bool droponfull[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS -1)] = SNDRV_SERIAL_NORMALBUFF };
+
+module_param_array(index, int, NULL, 0444);
+MODULE_PARM_DESC(index, "Index value for Serial MIDI.");
+module_param_array(id, charp, NULL, 0444);
+MODULE_PARM_DESC(id, "ID string for Serial MIDI.");
+module_param_array(enable, bool, NULL, 0444);
+MODULE_PARM_DESC(enable, "Enable UART16550A chip.");
+module_param_hw_array(port, long, ioport, NULL, 0444);
+MODULE_PARM_DESC(port, "Port # for UART16550A chip.");
+module_param_hw_array(irq, int, irq, NULL, 0444);
+MODULE_PARM_DESC(irq, "IRQ # for UART16550A chip.");
+module_param_array(speed, int, NULL, 0444);
+MODULE_PARM_DESC(speed, "Speed in bauds.");
+module_param_array(base, int, NULL, 0444);
+MODULE_PARM_DESC(base, "Base for divisor in bauds.");
+module_param_array(outs, int, NULL, 0444);
+MODULE_PARM_DESC(outs, "Number of MIDI outputs.");
+module_param_array(ins, int, NULL, 0444);
+MODULE_PARM_DESC(ins, "Number of MIDI inputs.");
+module_param_array(droponfull, bool, NULL, 0444);
+MODULE_PARM_DESC(droponfull, "Flag to enable drop-on-full buffer mode");
+
+module_param_array(adaptor, int, NULL, 0444);
+MODULE_PARM_DESC(adaptor, "Type of adaptor.");
+
+/*#define SNDRV_SERIAL_MS124W_MB_NOCOMBO 1*/ /* Address outs as 0-3 instead of bitmap */
+
+#define SNDRV_SERIAL_MAX_OUTS 16 /* max 64, min 16 */
+#define SNDRV_SERIAL_MAX_INS 16 /* max 64, min 16 */
+
+#define TX_BUFF_SIZE (1<<15) /* Must be 2^n */
+#define TX_BUFF_MASK (TX_BUFF_SIZE - 1)
+
+#define SERIAL_MODE_NOT_OPENED (0)
+#define SERIAL_MODE_INPUT_OPEN (1 << 0)
+#define SERIAL_MODE_OUTPUT_OPEN (1 << 1)
+#define SERIAL_MODE_INPUT_TRIGGERED (1 << 2)
+#define SERIAL_MODE_OUTPUT_TRIGGERED (1 << 3)
+
+struct snd_uart16550 {
+ struct snd_card *card;
+ struct snd_rawmidi *rmidi;
+ struct snd_rawmidi_substream *midi_output[SNDRV_SERIAL_MAX_OUTS];
+ struct snd_rawmidi_substream *midi_input[SNDRV_SERIAL_MAX_INS];
+
+ int filemode; /* open status of file */
+
+ spinlock_t open_lock;
+
+ int irq;
+
+ unsigned long base;
+ struct resource *res_base;
+
+ unsigned int speed;
+ unsigned int speed_base;
+ unsigned char divisor;
+
+ unsigned char old_divisor_lsb;
+ unsigned char old_divisor_msb;
+ unsigned char old_line_ctrl_reg;
+
+ /* parameter for using of write loop */
+ short int fifo_limit; /* used in uart16550 */
+ short int fifo_count; /* used in uart16550 */
+
+ /* type of adaptor */
+ int adaptor;
+
+ /* inputs */
+ int prev_in;
+ unsigned char rstatus;
+
+ /* outputs */
+ int prev_out;
+ unsigned char prev_status[SNDRV_SERIAL_MAX_OUTS];
+
+ /* write buffer and its writing/reading position */
+ unsigned char tx_buff[TX_BUFF_SIZE];
+ int buff_in_count;
+ int buff_in;
+ int buff_out;
+ int drop_on_full;
+
+ /* wait timer */
+ unsigned int timer_running:1;
+ struct timer_list buffer_timer;
+
+};
+
+static struct platform_device *devices[SNDRV_CARDS];
+
+static inline void snd_uart16550_add_timer(struct snd_uart16550 *uart)
+{
+ if (!uart->timer_running) {
+ /* timer 38600bps * 10bit * 16byte */
+ mod_timer(&uart->buffer_timer, jiffies + (HZ + 255) / 256);
+ uart->timer_running = 1;
+ }
+}
+
+static inline void snd_uart16550_del_timer(struct snd_uart16550 *uart)
+{
+ if (uart->timer_running) {
+ del_timer(&uart->buffer_timer);
+ uart->timer_running = 0;
+ }
+}
+
+/* This macro is only used in snd_uart16550_io_loop */
+static inline void snd_uart16550_buffer_output(struct snd_uart16550 *uart)
+{
+ unsigned short buff_out = uart->buff_out;
+ if (uart->buff_in_count > 0) {
+ outb(uart->tx_buff[buff_out], uart->base + UART_TX);
+ uart->fifo_count++;
+ buff_out++;
+ buff_out &= TX_BUFF_MASK;
+ uart->buff_out = buff_out;
+ uart->buff_in_count--;
+ }
+}
+
+/* This loop should be called with interrupts disabled
+ * We don't want to interrupt this,
+ * as we're already handling an interrupt
+ */
+static void snd_uart16550_io_loop(struct snd_uart16550 * uart)
+{
+ unsigned char c, status;
+ int substream;
+
+ /* recall previous stream */
+ substream = uart->prev_in;
+
+ /* Read Loop */
+ while ((status = inb(uart->base + UART_LSR)) & UART_LSR_DR) {
+ /* while receive data ready */
+ c = inb(uart->base + UART_RX);
+
+ /* keep track of last status byte */
+ if (c & 0x80)
+ uart->rstatus = c;
+
+ /* handle stream switch */
+ if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
+ if (uart->rstatus == 0xf5) {
+ if (c <= SNDRV_SERIAL_MAX_INS && c > 0)
+ substream = c - 1;
+ if (c != 0xf5)
+ /* prevent future bytes from being
+ interpreted as streams */
+ uart->rstatus = 0;
+ } else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN)
+ && uart->midi_input[substream])
+ snd_rawmidi_receive(uart->midi_input[substream],
+ &c, 1);
+ } else if ((uart->filemode & SERIAL_MODE_INPUT_OPEN) &&
+ uart->midi_input[substream])
+ snd_rawmidi_receive(uart->midi_input[substream], &c, 1);
+
+ if (status & UART_LSR_OE)
+ snd_printk(KERN_WARNING
+ "%s: Overrun on device at 0x%lx\n",
+ uart->rmidi->name, uart->base);
+ }
+
+ /* remember the last stream */
+ uart->prev_in = substream;
+
+ /* no need of check SERIAL_MODE_OUTPUT_OPEN because if not,
+ buffer is never filled. */
+ /* Check write status */
+ if (status & UART_LSR_THRE)
+ uart->fifo_count = 0;
+ if (uart->adaptor == SNDRV_SERIAL_MS124W_SA
+ || uart->adaptor == SNDRV_SERIAL_GENERIC) {
+ /* Can't use FIFO, must send only when CTS is true */
+ status = inb(uart->base + UART_MSR);
+ while (uart->fifo_count == 0 && (status & UART_MSR_CTS) &&
+ uart->buff_in_count > 0) {
+ snd_uart16550_buffer_output(uart);
+ status = inb(uart->base + UART_MSR);
+ }
+ } else {
+ /* Write loop */
+ while (uart->fifo_count < uart->fifo_limit /* Can we write ? */
+ && uart->buff_in_count > 0) /* Do we want to? */
+ snd_uart16550_buffer_output(uart);
+ }
+ if (uart->irq < 0 && uart->buff_in_count > 0)
+ snd_uart16550_add_timer(uart);
+}
+
+/* NOTES ON SERVICING INTERUPTS
+ * ---------------------------
+ * After receiving a interrupt, it is important to indicate to the UART that
+ * this has been done.
+ * For a Rx interrupt, this is done by reading the received byte.
+ * For a Tx interrupt this is done by either:
+ * a) Writing a byte
+ * b) Reading the IIR
+ * It is particularly important to read the IIR if a Tx interrupt is received
+ * when there is no data in tx_buff[], as in this case there no other
+ * indication that the interrupt has been serviced, and it remains outstanding
+ * indefinitely. This has the curious side effect that and no further interrupts
+ * will be generated from this device AT ALL!!.
+ * It is also desirable to clear outstanding interrupts when the device is
+ * opened/closed.
+ *
+ *
+ * Note that some devices need OUT2 to be set before they will generate
+ * interrupts at all. (Possibly tied to an internal pull-up on CTS?)
+ */
+static irqreturn_t snd_uart16550_interrupt(int irq, void *dev_id)
+{
+ struct snd_uart16550 *uart;
+
+ uart = dev_id;
+ spin_lock(&uart->open_lock);
+ if (uart->filemode == SERIAL_MODE_NOT_OPENED) {
+ spin_unlock(&uart->open_lock);
+ return IRQ_NONE;
+ }
+ /* indicate to the UART that the interrupt has been serviced */
+ inb(uart->base + UART_IIR);
+ snd_uart16550_io_loop(uart);
+ spin_unlock(&uart->open_lock);
+ return IRQ_HANDLED;
+}
+
+/* When the polling mode, this function calls snd_uart16550_io_loop. */
+static void snd_uart16550_buffer_timer(struct timer_list *t)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart;
+
+ uart = from_timer(uart, t, buffer_timer);
+ spin_lock_irqsave(&uart->open_lock, flags);
+ snd_uart16550_del_timer(uart);
+ snd_uart16550_io_loop(uart);
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+}
+
+/*
+ * this method probes, if an uart sits on given port
+ * return 0 if found
+ * return negative error if not found
+ */
+static int snd_uart16550_detect(struct snd_uart16550 *uart)
+{
+ unsigned long io_base = uart->base;
+ int ok;
+ unsigned char c;
+
+ /* Do some vague tests for the presence of the uart */
+ if (io_base == 0 || io_base == SNDRV_AUTO_PORT) {
+ return -ENODEV; /* Not configured */
+ }
+
+ uart->res_base = request_region(io_base, 8, "Serial MIDI");
+ if (uart->res_base == NULL) {
+ snd_printk(KERN_ERR "u16550: can't grab port 0x%lx\n", io_base);
+ return -EBUSY;
+ }
+
+ /* uart detected unless one of the following tests should fail */
+ ok = 1;
+ /* 8 data-bits, 1 stop-bit, parity off, DLAB = 0 */
+ outb(UART_LCR_WLEN8, io_base + UART_LCR); /* Line Control Register */
+ c = inb(io_base + UART_IER);
+ /* The top four bits of the IER should always == 0 */
+ if ((c & 0xf0) != 0)
+ ok = 0; /* failed */
+
+ outb(0xaa, io_base + UART_SCR);
+ /* Write arbitrary data into the scratch reg */
+ c = inb(io_base + UART_SCR);
+ /* If it comes back, it's OK */
+ if (c != 0xaa)
+ ok = 0; /* failed */
+
+ outb(0x55, io_base + UART_SCR);
+ /* Write arbitrary data into the scratch reg */
+ c = inb(io_base + UART_SCR);
+ /* If it comes back, it's OK */
+ if (c != 0x55)
+ ok = 0; /* failed */
+
+ return ok;
+}
+
+static void snd_uart16550_do_open(struct snd_uart16550 * uart)
+{
+ char byte;
+
+ /* Initialize basic variables */
+ uart->buff_in_count = 0;
+ uart->buff_in = 0;
+ uart->buff_out = 0;
+ uart->fifo_limit = 1;
+ uart->fifo_count = 0;
+ uart->timer_running = 0;
+
+ outb(UART_FCR_ENABLE_FIFO /* Enable FIFO's (if available) */
+ | UART_FCR_CLEAR_RCVR /* Clear receiver FIFO */
+ | UART_FCR_CLEAR_XMIT /* Clear transmitter FIFO */
+ | UART_FCR_TRIGGER_4 /* Set FIFO trigger at 4-bytes */
+ /* NOTE: interrupt generated after T=(time)4-bytes
+ * if less than UART_FCR_TRIGGER bytes received
+ */
+ ,uart->base + UART_FCR); /* FIFO Control Register */
+
+ if ((inb(uart->base + UART_IIR) & 0xf0) == 0xc0)
+ uart->fifo_limit = 16;
+ if (uart->divisor != 0) {
+ uart->old_line_ctrl_reg = inb(uart->base + UART_LCR);
+ outb(UART_LCR_DLAB /* Divisor latch access bit */
+ ,uart->base + UART_LCR); /* Line Control Register */
+ uart->old_divisor_lsb = inb(uart->base + UART_DLL);
+ uart->old_divisor_msb = inb(uart->base + UART_DLM);
+
+ outb(uart->divisor
+ ,uart->base + UART_DLL); /* Divisor Latch Low */
+ outb(0
+ ,uart->base + UART_DLM); /* Divisor Latch High */
+ /* DLAB is reset to 0 in next outb() */
+ }
+ /* Set serial parameters (parity off, etc) */
+ outb(UART_LCR_WLEN8 /* 8 data-bits */
+ | 0 /* 1 stop-bit */
+ | 0 /* parity off */
+ | 0 /* DLAB = 0 */
+ ,uart->base + UART_LCR); /* Line Control Register */
+
+ switch (uart->adaptor) {
+ default:
+ outb(UART_MCR_RTS /* Set Request-To-Send line active */
+ | UART_MCR_DTR /* Set Data-Terminal-Ready line active */
+ | UART_MCR_OUT2 /* Set OUT2 - not always required, but when
+ * it is, it is ESSENTIAL for enabling interrupts
+ */
+ ,uart->base + UART_MCR); /* Modem Control Register */
+ break;
+ case SNDRV_SERIAL_MS124W_SA:
+ case SNDRV_SERIAL_MS124W_MB:
+ /* MS-124W can draw power from RTS and DTR if they
+ are in opposite states. */
+ outb(UART_MCR_RTS | (0&UART_MCR_DTR) | UART_MCR_OUT2,
+ uart->base + UART_MCR);
+ break;
+ case SNDRV_SERIAL_MS124T:
+ /* MS-124T can draw power from RTS and/or DTR (preferably
+ both) if they are both asserted. */
+ outb(UART_MCR_RTS | UART_MCR_DTR | UART_MCR_OUT2,
+ uart->base + UART_MCR);
+ break;
+ }
+
+ if (uart->irq < 0) {
+ byte = (0 & UART_IER_RDI) /* Disable Receiver data interrupt */
+ |(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
+ ;
+ } else if (uart->adaptor == SNDRV_SERIAL_MS124W_SA) {
+ byte = UART_IER_RDI /* Enable Receiver data interrupt */
+ | UART_IER_MSI /* Enable Modem status interrupt */
+ ;
+ } else if (uart->adaptor == SNDRV_SERIAL_GENERIC) {
+ byte = UART_IER_RDI /* Enable Receiver data interrupt */
+ | UART_IER_MSI /* Enable Modem status interrupt */
+ | UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
+ ;
+ } else {
+ byte = UART_IER_RDI /* Enable Receiver data interrupt */
+ | UART_IER_THRI /* Enable Transmitter holding register empty interrupt */
+ ;
+ }
+ outb(byte, uart->base + UART_IER); /* Interrupt enable Register */
+
+ inb(uart->base + UART_LSR); /* Clear any pre-existing overrun indication */
+ inb(uart->base + UART_IIR); /* Clear any pre-existing transmit interrupt */
+ inb(uart->base + UART_RX); /* Clear any pre-existing receive interrupt */
+}
+
+static void snd_uart16550_do_close(struct snd_uart16550 * uart)
+{
+ if (uart->irq < 0)
+ snd_uart16550_del_timer(uart);
+
+ /* NOTE: may need to disable interrupts before de-registering out handler.
+ * For now, the consequences are harmless.
+ */
+
+ outb((0 & UART_IER_RDI) /* Disable Receiver data interrupt */
+ |(0 & UART_IER_THRI) /* Disable Transmitter holding register empty interrupt */
+ ,uart->base + UART_IER); /* Interrupt enable Register */
+
+ switch (uart->adaptor) {
+ default:
+ outb((0 & UART_MCR_RTS) /* Deactivate Request-To-Send line */
+ |(0 & UART_MCR_DTR) /* Deactivate Data-Terminal-Ready line */
+ |(0 & UART_MCR_OUT2) /* Deactivate OUT2 */
+ ,uart->base + UART_MCR); /* Modem Control Register */
+ break;
+ case SNDRV_SERIAL_MS124W_SA:
+ case SNDRV_SERIAL_MS124W_MB:
+ /* MS-124W can draw power from RTS and DTR if they
+ are in opposite states; leave it powered. */
+ outb(UART_MCR_RTS | (0&UART_MCR_DTR) | (0&UART_MCR_OUT2),
+ uart->base + UART_MCR);
+ break;
+ case SNDRV_SERIAL_MS124T:
+ /* MS-124T can draw power from RTS and/or DTR (preferably
+ both) if they are both asserted; leave it powered. */
+ outb(UART_MCR_RTS | UART_MCR_DTR | (0&UART_MCR_OUT2),
+ uart->base + UART_MCR);
+ break;
+ }
+
+ inb(uart->base + UART_IIR); /* Clear any outstanding interrupts */
+
+ /* Restore old divisor */
+ if (uart->divisor != 0) {
+ outb(UART_LCR_DLAB /* Divisor latch access bit */
+ ,uart->base + UART_LCR); /* Line Control Register */
+ outb(uart->old_divisor_lsb
+ ,uart->base + UART_DLL); /* Divisor Latch Low */
+ outb(uart->old_divisor_msb
+ ,uart->base + UART_DLM); /* Divisor Latch High */
+ /* Restore old LCR (data bits, stop bits, parity, DLAB) */
+ outb(uart->old_line_ctrl_reg
+ ,uart->base + UART_LCR); /* Line Control Register */
+ }
+}
+
+static int snd_uart16550_input_open(struct snd_rawmidi_substream *substream)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ if (uart->filemode == SERIAL_MODE_NOT_OPENED)
+ snd_uart16550_do_open(uart);
+ uart->filemode |= SERIAL_MODE_INPUT_OPEN;
+ uart->midi_input[substream->number] = substream;
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+ return 0;
+}
+
+static int snd_uart16550_input_close(struct snd_rawmidi_substream *substream)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ uart->filemode &= ~SERIAL_MODE_INPUT_OPEN;
+ uart->midi_input[substream->number] = NULL;
+ if (uart->filemode == SERIAL_MODE_NOT_OPENED)
+ snd_uart16550_do_close(uart);
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+ return 0;
+}
+
+static void snd_uart16550_input_trigger(struct snd_rawmidi_substream *substream,
+ int up)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ if (up)
+ uart->filemode |= SERIAL_MODE_INPUT_TRIGGERED;
+ else
+ uart->filemode &= ~SERIAL_MODE_INPUT_TRIGGERED;
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+}
+
+static int snd_uart16550_output_open(struct snd_rawmidi_substream *substream)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ if (uart->filemode == SERIAL_MODE_NOT_OPENED)
+ snd_uart16550_do_open(uart);
+ uart->filemode |= SERIAL_MODE_OUTPUT_OPEN;
+ uart->midi_output[substream->number] = substream;
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+ return 0;
+};
+
+static int snd_uart16550_output_close(struct snd_rawmidi_substream *substream)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ uart->filemode &= ~SERIAL_MODE_OUTPUT_OPEN;
+ uart->midi_output[substream->number] = NULL;
+ if (uart->filemode == SERIAL_MODE_NOT_OPENED)
+ snd_uart16550_do_close(uart);
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+ return 0;
+};
+
+static inline int snd_uart16550_buffer_can_write(struct snd_uart16550 *uart,
+ int Num)
+{
+ if (uart->buff_in_count + Num < TX_BUFF_SIZE)
+ return 1;
+ else
+ return 0;
+}
+
+static inline int snd_uart16550_write_buffer(struct snd_uart16550 *uart,
+ unsigned char byte)
+{
+ unsigned short buff_in = uart->buff_in;
+ if (uart->buff_in_count < TX_BUFF_SIZE) {
+ uart->tx_buff[buff_in] = byte;
+ buff_in++;
+ buff_in &= TX_BUFF_MASK;
+ uart->buff_in = buff_in;
+ uart->buff_in_count++;
+ if (uart->irq < 0) /* polling mode */
+ snd_uart16550_add_timer(uart);
+ return 1;
+ } else
+ return 0;
+}
+
+static int snd_uart16550_output_byte(struct snd_uart16550 *uart,
+ struct snd_rawmidi_substream *substream,
+ unsigned char midi_byte)
+{
+ if (uart->buff_in_count == 0 /* Buffer empty? */
+ && ((uart->adaptor != SNDRV_SERIAL_MS124W_SA &&
+ uart->adaptor != SNDRV_SERIAL_GENERIC) ||
+ (uart->fifo_count == 0 /* FIFO empty? */
+ && (inb(uart->base + UART_MSR) & UART_MSR_CTS)))) { /* CTS? */
+
+ /* Tx Buffer Empty - try to write immediately */
+ if ((inb(uart->base + UART_LSR) & UART_LSR_THRE) != 0) {
+ /* Transmitter holding register (and Tx FIFO) empty */
+ uart->fifo_count = 1;
+ outb(midi_byte, uart->base + UART_TX);
+ } else {
+ if (uart->fifo_count < uart->fifo_limit) {
+ uart->fifo_count++;
+ outb(midi_byte, uart->base + UART_TX);
+ } else {
+ /* Cannot write (buffer empty) -
+ * put char in buffer */
+ snd_uart16550_write_buffer(uart, midi_byte);
+ }
+ }
+ } else {
+ if (!snd_uart16550_write_buffer(uart, midi_byte)) {
+ snd_printk(KERN_WARNING
+ "%s: Buffer overrun on device at 0x%lx\n",
+ uart->rmidi->name, uart->base);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static void snd_uart16550_output_write(struct snd_rawmidi_substream *substream)
+{
+ unsigned long flags;
+ unsigned char midi_byte, addr_byte;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+ char first;
+ static unsigned long lasttime = 0;
+
+ /* Interrupts are disabled during the updating of the tx_buff,
+ * since it is 'bad' to have two processes updating the same
+ * variables (ie buff_in & buff_out)
+ */
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+
+ if (uart->irq < 0) /* polling */
+ snd_uart16550_io_loop(uart);
+
+ if (uart->adaptor == SNDRV_SERIAL_MS124W_MB) {
+ while (1) {
+ /* buffer full? */
+ /* in this mode we need two bytes of space */
+ if (uart->buff_in_count > TX_BUFF_SIZE - 2)
+ break;
+ if (snd_rawmidi_transmit(substream, &midi_byte, 1) != 1)
+ break;
+#ifdef SNDRV_SERIAL_MS124W_MB_NOCOMBO
+ /* select exactly one of the four ports */
+ addr_byte = (1 << (substream->number + 4)) | 0x08;
+#else
+ /* select any combination of the four ports */
+ addr_byte = (substream->number << 4) | 0x08;
+ /* ...except none */
+ if (addr_byte == 0x08)
+ addr_byte = 0xf8;
+#endif
+ snd_uart16550_output_byte(uart, substream, addr_byte);
+ /* send midi byte */
+ snd_uart16550_output_byte(uart, substream, midi_byte);
+ }
+ } else {
+ first = 0;
+ while (snd_rawmidi_transmit_peek(substream, &midi_byte, 1) == 1) {
+ /* Also send F5 after 3 seconds with no data
+ * to handle device disconnect */
+ if (first == 0 &&
+ (uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS ||
+ uart->adaptor == SNDRV_SERIAL_GENERIC) &&
+ (uart->prev_out != substream->number ||
+ time_after(jiffies, lasttime + 3*HZ))) {
+
+ if (snd_uart16550_buffer_can_write(uart, 3)) {
+ /* Roland Soundcanvas part selection */
+ /* If this substream of the data is
+ * different previous substream
+ * in this uart, send the change part
+ * event
+ */
+ uart->prev_out = substream->number;
+ /* change part */
+ snd_uart16550_output_byte(uart, substream,
+ 0xf5);
+ /* data */
+ snd_uart16550_output_byte(uart, substream,
+ uart->prev_out + 1);
+ /* If midi_byte is a data byte,
+ * send the previous status byte */
+ if (midi_byte < 0x80 &&
+ uart->adaptor == SNDRV_SERIAL_SOUNDCANVAS)
+ snd_uart16550_output_byte(uart, substream, uart->prev_status[uart->prev_out]);
+ } else if (!uart->drop_on_full)
+ break;
+
+ }
+
+ /* send midi byte */
+ if (!snd_uart16550_output_byte(uart, substream, midi_byte) &&
+ !uart->drop_on_full )
+ break;
+
+ if (midi_byte >= 0x80 && midi_byte < 0xf0)
+ uart->prev_status[uart->prev_out] = midi_byte;
+ first = 1;
+
+ snd_rawmidi_transmit_ack( substream, 1 );
+ }
+ lasttime = jiffies;
+ }
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+}
+
+static void snd_uart16550_output_trigger(struct snd_rawmidi_substream *substream,
+ int up)
+{
+ unsigned long flags;
+ struct snd_uart16550 *uart = substream->rmidi->private_data;
+
+ spin_lock_irqsave(&uart->open_lock, flags);
+ if (up)
+ uart->filemode |= SERIAL_MODE_OUTPUT_TRIGGERED;
+ else
+ uart->filemode &= ~SERIAL_MODE_OUTPUT_TRIGGERED;
+ spin_unlock_irqrestore(&uart->open_lock, flags);
+ if (up)
+ snd_uart16550_output_write(substream);
+}
+
+static const struct snd_rawmidi_ops snd_uart16550_output =
+{
+ .open = snd_uart16550_output_open,
+ .close = snd_uart16550_output_close,
+ .trigger = snd_uart16550_output_trigger,
+};
+
+static const struct snd_rawmidi_ops snd_uart16550_input =
+{
+ .open = snd_uart16550_input_open,
+ .close = snd_uart16550_input_close,
+ .trigger = snd_uart16550_input_trigger,
+};
+
+static int snd_uart16550_free(struct snd_uart16550 *uart)
+{
+ if (uart->irq >= 0)
+ free_irq(uart->irq, uart);
+ release_and_free_resource(uart->res_base);
+ kfree(uart);
+ return 0;
+};
+
+static int snd_uart16550_dev_free(struct snd_device *device)
+{
+ struct snd_uart16550 *uart = device->device_data;
+ return snd_uart16550_free(uart);
+}
+
+static int snd_uart16550_create(struct snd_card *card,
+ unsigned long iobase,
+ int irq,
+ unsigned int speed,
+ unsigned int base,
+ int adaptor,
+ int droponfull,
+ struct snd_uart16550 **ruart)
+{
+ static const struct snd_device_ops ops = {
+ .dev_free = snd_uart16550_dev_free,
+ };
+ struct snd_uart16550 *uart;
+ int err;
+
+
+ if ((uart = kzalloc(sizeof(*uart), GFP_KERNEL)) == NULL)
+ return -ENOMEM;
+ uart->adaptor = adaptor;
+ uart->card = card;
+ spin_lock_init(&uart->open_lock);
+ uart->irq = -1;
+ uart->base = iobase;
+ uart->drop_on_full = droponfull;
+
+ if ((err = snd_uart16550_detect(uart)) <= 0) {
+ printk(KERN_ERR "no UART detected at 0x%lx\n", iobase);
+ snd_uart16550_free(uart);
+ return -ENODEV;
+ }
+
+ if (irq >= 0 && irq != SNDRV_AUTO_IRQ) {
+ if (request_irq(irq, snd_uart16550_interrupt,
+ 0, "Serial MIDI", uart)) {
+ snd_printk(KERN_WARNING
+ "irq %d busy. Using Polling.\n", irq);
+ } else {
+ uart->irq = irq;
+ }
+ }
+ uart->divisor = base / speed;
+ uart->speed = base / (unsigned int)uart->divisor;
+ uart->speed_base = base;
+ uart->prev_out = -1;
+ uart->prev_in = 0;
+ uart->rstatus = 0;
+ memset(uart->prev_status, 0x80, sizeof(unsigned char) * SNDRV_SERIAL_MAX_OUTS);
+ timer_setup(&uart->buffer_timer, snd_uart16550_buffer_timer, 0);
+ uart->timer_running = 0;
+
+ /* Register device */
+ if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, uart, &ops)) < 0) {
+ snd_uart16550_free(uart);
+ return err;
+ }
+
+ switch (uart->adaptor) {
+ case SNDRV_SERIAL_MS124W_SA:
+ case SNDRV_SERIAL_MS124W_MB:
+ /* MS-124W can draw power from RTS and DTR if they
+ are in opposite states. */
+ outb(UART_MCR_RTS | (0&UART_MCR_DTR), uart->base + UART_MCR);
+ break;
+ case SNDRV_SERIAL_MS124T:
+ /* MS-124T can draw power from RTS and/or DTR (preferably
+ both) if they are asserted. */
+ outb(UART_MCR_RTS | UART_MCR_DTR, uart->base + UART_MCR);
+ break;
+ default:
+ break;
+ }
+
+ if (ruart)
+ *ruart = uart;
+
+ return 0;
+}
+
+static void snd_uart16550_substreams(struct snd_rawmidi_str *stream)
+{
+ struct snd_rawmidi_substream *substream;
+
+ list_for_each_entry(substream, &stream->substreams, list) {
+ sprintf(substream->name, "Serial MIDI %d", substream->number + 1);
+ }
+}
+
+static int snd_uart16550_rmidi(struct snd_uart16550 *uart, int device,
+ int outs, int ins,
+ struct snd_rawmidi **rmidi)
+{
+ struct snd_rawmidi *rrawmidi;
+ int err;
+
+ err = snd_rawmidi_new(uart->card, "UART Serial MIDI", device,
+ outs, ins, &rrawmidi);
+ if (err < 0)
+ return err;
+ snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+ &snd_uart16550_input);
+ snd_rawmidi_set_ops(rrawmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
+ &snd_uart16550_output);
+ strcpy(rrawmidi->name, "Serial MIDI");
+ snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
+ snd_uart16550_substreams(&rrawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
+ rrawmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
+ SNDRV_RAWMIDI_INFO_INPUT |
+ SNDRV_RAWMIDI_INFO_DUPLEX;
+ rrawmidi->private_data = uart;
+ if (rmidi)
+ *rmidi = rrawmidi;
+ return 0;
+}
+
+static int snd_serial_probe(struct platform_device *devptr)
+{
+ struct snd_card *card;
+ struct snd_uart16550 *uart;
+ int err;
+ int dev = devptr->id;
+
+ switch (adaptor[dev]) {
+ case SNDRV_SERIAL_SOUNDCANVAS:
+ ins[dev] = 1;
+ break;
+ case SNDRV_SERIAL_MS124T:
+ case SNDRV_SERIAL_MS124W_SA:
+ outs[dev] = 1;
+ ins[dev] = 1;
+ break;
+ case SNDRV_SERIAL_MS124W_MB:
+ outs[dev] = 16;
+ ins[dev] = 1;
+ break;
+ case SNDRV_SERIAL_GENERIC:
+ break;
+ default:
+ snd_printk(KERN_ERR
+ "Adaptor type is out of range 0-%d (%d)\n",
+ SNDRV_SERIAL_MAX_ADAPTOR, adaptor[dev]);
+ return -ENODEV;
+ }
+
+ if (outs[dev] < 1 || outs[dev] > SNDRV_SERIAL_MAX_OUTS) {
+ snd_printk(KERN_ERR
+ "Count of outputs is out of range 1-%d (%d)\n",
+ SNDRV_SERIAL_MAX_OUTS, outs[dev]);
+ return -ENODEV;
+ }
+
+ if (ins[dev] < 1 || ins[dev] > SNDRV_SERIAL_MAX_INS) {
+ snd_printk(KERN_ERR
+ "Count of inputs is out of range 1-%d (%d)\n",
+ SNDRV_SERIAL_MAX_INS, ins[dev]);
+ return -ENODEV;
+ }
+
+ err = snd_card_new(&devptr->dev, index[dev], id[dev], THIS_MODULE,
+ 0, &card);
+ if (err < 0)
+ return err;
+
+ strcpy(card->driver, "Serial");
+ strcpy(card->shortname, "Serial MIDI (UART16550A)");
+
+ if ((err = snd_uart16550_create(card,
+ port[dev],
+ irq[dev],
+ speed[dev],
+ base[dev],
+ adaptor[dev],
+ droponfull[dev],
+ &uart)) < 0)
+ goto _err;
+
+ err = snd_uart16550_rmidi(uart, 0, outs[dev], ins[dev], &uart->rmidi);
+ if (err < 0)
+ goto _err;
+
+ sprintf(card->longname, "%s [%s] at %#lx, irq %d",
+ card->shortname,
+ adaptor_names[uart->adaptor],
+ uart->base,
+ uart->irq);
+
+ if ((err = snd_card_register(card)) < 0)
+ goto _err;
+
+ platform_set_drvdata(devptr, card);
+ return 0;
+
+ _err:
+ snd_card_free(card);
+ return err;
+}
+
+static int snd_serial_remove(struct platform_device *devptr)
+{
+ snd_card_free(platform_get_drvdata(devptr));
+ return 0;
+}
+
+#define SND_SERIAL_DRIVER "snd_serial_u16550"
+
+static struct platform_driver snd_serial_driver = {
+ .probe = snd_serial_probe,
+ .remove = snd_serial_remove,
+ .driver = {
+ .name = SND_SERIAL_DRIVER,
+ },
+};
+
+static void snd_serial_unregister_all(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(devices); ++i)
+ platform_device_unregister(devices[i]);
+ platform_driver_unregister(&snd_serial_driver);
+}
+
+static int __init alsa_card_serial_init(void)
+{
+ int i, cards, err;
+
+ if ((err = platform_driver_register(&snd_serial_driver)) < 0)
+ return err;
+
+ cards = 0;
+ for (i = 0; i < SNDRV_CARDS; i++) {
+ struct platform_device *device;
+ if (! enable[i])
+ continue;
+ device = platform_device_register_simple(SND_SERIAL_DRIVER,
+ i, NULL, 0);
+ if (IS_ERR(device))
+ continue;
+ if (!platform_get_drvdata(device)) {
+ platform_device_unregister(device);
+ continue;
+ }
+ devices[i] = device;
+ cards++;
+ }
+ if (! cards) {
+#ifdef MODULE
+ printk(KERN_ERR "serial midi soundcard not found or device busy\n");
+#endif
+ snd_serial_unregister_all();
+ return -ENODEV;
+ }
+ return 0;
+}
+
+static void __exit alsa_card_serial_exit(void)
+{
+ snd_serial_unregister_all();
+}
+
+module_init(alsa_card_serial_init)
+module_exit(alsa_card_serial_exit)